That was part of what they told us at that meeting we had last semester. They're starting it this year. I don't remember them saying it was due to low scores though, as much as to safeguard against low scores due to the new regulations the medical board has put on med schools, where ones with too low a pass rate (USMLE) would have their accreditation retracted (both in and outside the US). Not sure on the details, as the meeting was a while back, but that's the gist I remember.
Did you go to yesterday's meeting? I was going to but got burned out in biochem lab and decided to go home and nurse my migraine instead >_<. I know a couple second years who did go, however, so I'm waiting on their intel ^_^.
Either way the exam seems like good USMLE prep. Personally I much rather find out then if i'm not ready fur the USMLE than after taking the real exam ^_~.